A Seleucid army of ~200 BC was invading Ptolemaic Egypt, somehow ending up facing the army of Ptolemy on the south bank of the Nile. We believe Eratosthenes is somehow to blame. The games used the 1.0 rules.
The only terrain to prove relevant during the battle was a stretch of rocky ground (RF) in the Ptolemaic deployment zone. The Ptolemaics put their phalanx (all Pk (O) Macedonians and mercenaries) on the left, with a few thyreophoroi to protect the flank, the CinC's command of thyreophoroi in the centre in the rocky ground, and the mounted command (Reg Kn (F) in single-element wedges plus a few Cv (O)) in column on the right.
The Seleucids put their smaller but deeper phalanx (1/3 Pk (S) argyraspides, rest Pk (O)) opposite the rightmost part of the Ptolemaic phalanx. On each wing went a command with 3 cataphract elements (incl generals) and one of elephants; the right wing also had a few thyreophoroi while the left had some Asiatic horse archers. The left wing was opposite the Ptolemaic thyreophoros command, meaning the Ptolemaic mounted would have plenty of space to envelope it.
The basic tactics each side would have to use were thus clear from deployment; the Seleucids would try and break through the Ptolemaic phalanx - which had sacrificed depth for width - before their left wing was overwhelmed by the more numerous (and effectively better quality as Kn (X) count as inferior against Kn (F)) enemy mounted, while the Ptolemaics would have to hope their phalangites could hold out till the mounted swept away the Seleucid left and fell the rest of the army in the rear. Clearly, the single El (S) element of the Seleucid left would play an important role here, as the only element of that wing the Ptolemaic lancers would have to truly fear.
The Seleucids accordingly rushed forward with their phalanx and right wing, while echeloning back the left to postpone envelopment by the Ptolemaic mounted while still pinning the thyreophoroi in the rocky ground and keeping them from hitting the phalanx's flank. The Ptolemaics meanwhile moved their mounted forward and reformed them into an oblique line facing the now-angled Seleucid left.
The first contact was between the Ptolemaic phalanx and the Seleucid pike and mounted facing it. The cataphracts did very little impression and the phalangites, despite the advantage of a fourth rank and some of their numbers being Superior, made very slow headway against their Ptolemaic equivalents. The elephants, however, started to punch a hole through the Ptolemaic line while the thyreophoroi (with some help from the cataphracts) beat their opposite numbers and started to roll up the Ptolemaics' flank.
Meanwhile, the Ptolemaic mounted hit the Seleucid left. The Skythians were swiftly destroyed by the mercenary cavalry, but one element of xystophoroi were destroyed by the elephants, while another xystophoros element was lost against the cataphracts, one element of which was also eliminated. Both commands were now disheartend (which didn't however affect the Seleucids as the only elements of <2 ME were the now-destroyed Skythians!) and close to breaking.
The elephants now saw an opportunity to decide the issue by trampling the Ptolemaic sub-general commanding their right, attacking him at 5(S):4(F), but the dice wouldn't cooperate and instead the pachyderms were surrounded by Ptolemaic troops and destroyed, breaking the Seleucid left wing.
Over on the Seleucid's right, the other elephant element had now smashed straight through the Ptolemaic line, and hit the flank of the Ptolemaic Pk sub-general, who was frontally engaged by the Seleucid phalanx. Again, however, the dice was with Ptolemy and the general won the combat, recoiling behind the left part of the Ptolemaic phalanx, whose rear rank was out of the threat zones of the recoiled cataphracts and thus able to turn around to surround and eliminate the elephants.
This was the Ptolemaics' last hurrah, however, as these troops were now attacked in the rear by the Seleucid thyreophoroi, while the front rank, now bereft of rear support, finally suffered some losses to the umpteenth charge of the cataphracts. The accumulated losses finally broke the Ptolemaic phalanx, and the knock-on effect put the right wing over the edge, which in turned caused the whole army to break.
The Seleucids had lost the left wing (12 ME) plus 3 ME from the other two commands, for a total of 15 out of 39.5. With one command broken, this amounts to a 18-7 win.
While luck played a part both ways - the cataphracts did notably poorly against the phalangites and remarkably well against the xystophoroi, while both Ptolemaic subbies were lucky to survive close encounters of the elephant kind - perhaps the most notable feature of the battle and an important contributor to the Seleucid victory was that while practically every Seleucid element fought, an entire command of the Ptolemaic army did nothing but provide overlaps against the Seleucid phalanx. While using one's entire army against part of theirs is by no means a guarantee of success, it's usually helpful.
